1. Field of the Invention
The present invention relates to a rolling bearing assembly for rotatably supporting, for example, a machine tool spindle and, more particularly, to a rolling bearing assembly capable of being used with, for example, a vertical spindle and also to a lubricating structure used in such rolling bearing assembly.
2. Description of Related Art
A lubricating device having a mechanism capable of not only cooling a bearing assembly but also supplying and discharging a lubricant oil to and from the bearing assembly has been suggested in, for example, the patent document 1 listed below. In this lubricating device, as shown in FIG. 46A of the accompanying drawings, the use is made of an inner ring spacer 50, which is held in contact with an inner ring end face, and a lubricant oil introducing member 51 which is held in contact with an outer ring end face. A circumferentially extending groove 53 is defined in an inclined face of the inner ring 52 that is continued from the inner ring end face towards an inner ring raceway surface and, at the same time, a nozzle 54 is provided in the lubricant oil introducing member 51, so that a lubricant oil concurrently serving as a bearing cooling medium can be jetted from the nozzle 54 into the circumferentially extending groove 53. In that figure, the arrow headed lines represent the direction of flow of the lubricant oil. When the lubricant oil introduced into the lubricant oil introducing member 51 is jetted into the circumferentially extending groove 53, the inner ring 52 can be cooled. A portion of the lubricant oil within the circumferentially extending groove 53 is supplied into the bearing assembly through a gap delimited by a overhanging portion 55, which extends from the lubricant introducing member 51 into the inside of the bearing assembly, and the inclined face referred to above.